The objective of this research is to conduct a detailed investigation into the mechanisms of mutagenesis of a series of carbonyl compounds known or suspected to pose threats to human health. In order to accomplish this goal, we propose to use the tools of organic synthesis and recombinant DNA technology to construct viral and plasmid DNA molecules that contain, at specific genome locations, the known DNA adducts formed by these compounds. These structurally altered genomes will be introduced into bacterial cells, where the single DNA lesion will be acted upon in a presumably normal way by the cell's replication/repair systems. Finally, we shall characterize the amount and type of mutations induced through misreplication or misrepair of the genome, and with this information, we shall attempt to establish formal rules that relate the structure of the DNA lesion, and possibly its persistence in DNA, with its biological effects. In parallel with studies on site-specifically altered genomes, the mutagenic activity of carbonyl compounds will be evaluated in a recently developed plasmid-based mutation assay. Unlike the aforementioned studies on the genetic effects of individual adducts, these studies will reveal the total spectrum of mutations that issue from biological processing of the collection of adducts created by DNA modification.